<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div id="app">
    {{fullName}}
</div>
<script src="../js/vue.js"></script>
<script>
    const aaa = new Vue({
        el:"#app",
        data:{
            firstName:"Kobe",
            lastName:"Bryant"
        },
        computed:{
            fullName:{
                set:function (newValue) {
                    const names = newValue.split(' ');
                    this.firstName = names[0];
                    this.lastName = names[1];
                },
                get:function () {
                    return this.firstName + ' ' + this.lastName;
                }
            }
        }
    })
</script>

</body>
</html>